The present invention relates to the field of LED display systems and data communications. More specifically, the invention provides a tricolor light emitting diode (xe2x80x9cLEDxe2x80x9d) display system in which the LEDs are used as concurrent display and data communication elements for displaying visible information and for transmitting modulated audio information to an associated receiver.
A tricolor LED display system is provided having a plurality of multi-color LEDs that operate as concurrent display and data communication elements. These dual-use tricolor LEDs are coupled to a special-purpose computer system and audio signal transmitter for simultaneously controlling the visible display signal from the LEDs, and for modulating audio information onto the visible light signal emitted by the LEDs. A receiver receives the modulated visible light signal from the LEDs and demodulates the received signal to recover the audio information, which is then presented to a user of the system through an audio interface.
The LED display system preferably includes a transmitter sub-system and a receiver sub-system. The transmitter subsystem may include a special-purpose computer, such as a PC, workstation or embedded computer, and an audio signal transmitter, which are both coupled to the preferred tricolor dot matrix LED display via a special interface circuit. The audio signal transmitter preferably includes a voltage-controlled oscillator for modulating the audio signal information onto the LEDs of the display. The preferred tricolor LED display is capable of generating three distinct colorsxe2x80x94red, green and amber. The receiver subsystem may include a lens for focusing the transmitted light from the LEDs onto a photo-detector (or other optical detection means), a demodulator circuit for recovering the audio information from the modulated visible light signal emitted by the tricolor display, and an audio system for presenting the demodulated audio information to a user of the system.
According to one aspect of the invention, a tricolor LED display system is provided that includes a transmitter sub-system for simultaneously transmitting visible display signals and modulated visible light signals through a tricolor LED display, wherein the modulated visible light signals carry modulated audio information; and a receiver sub-system for receiving the modulated visible light signals and for demodulating the visible light signals to recover the transmitted audio information.
According to another aspect of the invention, a tricolor LED display system is provided that includes a tricolor LED dot matrix display having a plurality of tricolor LEDs; means for applying a display signal to the tricolor LEDs to generate a visible signal pattern; and means for applying an audio signal to the tricolor LEDs to emit a modulated visible light signal that carries the audio signal.
Still another aspect of the invention provides an interface circuit for controlling a tricolor LED display, comprising: a row counter decode system coupled to a modulated audio signal for controlling the row selection of the LEDs in the tricolor LED display; and a segment counter decode system coupled to display information for controlling the segment selection of the LEDs in the tricolor LED display. The interface may also include: a parallel port interface for receiving the display information, the display information including display data and addressing information for the LED display; an address comparison unit for comparing the addressing information for the LED display with system addressing information generated by the row counter decode system and the segment counter decode system; and a pattern storage system for storing the display data when the address comparison unit indicates that the addressing information for the LED display is the same as the addressing information generated by the row counter decode system and the segment counter decode system.
It should be noted that these are just some of the many aspects of the present invention. Other aspects not specifically listed will become apparent upon reading the detailed description set forth below.
The present invention provides many advantages overly presently known data communication systems and LED display systems. Not all of these advantages are simultaneously required to practice the invention as claimed, and the following list is merely illustrative of the types of benefits that may be provided, alone or in combination. A primary advantage of the present invention is in the use of tricolor LEDs as the concurrent display and data communication elements. This provides a data communication system that is more reliable. Because tricolor LEDs are utilized in the display of the invention, the background of the display can be energized using a color that is different from the main characters (or messages) being displayed. LEDs in a given row (regardless of color state) can be modulated with the same audio information. By constructing the system in this manner, there will always be an LED lit up in each row, thus ensuring more reliable data transmission over single-color displays, in which certain LEDs in a row have to be shut off in order to provide the correct visible display. In addition to this reliability advantage, the pattern or graphics displayed by the tricolor display will also be more attractive and flexible as more colors can be used for the display.
Other advantages of this invention include, for example: (1) a brighter display than a single-color LED display; (2) reduced noise on the modulated signal due to the design of the interface circuit and its synchronization source; (3) permits text scrolling with no effect on the transmitted modulated signal; and (4) relaxed design constraints on the receiver system.
These are just a few of the many advantages of the present invention, as described in more detail below in terms of the preferred embodiments. As will be appreciated, the invention is capable of other and different embodiments than those specifically set forth below, and its details are capable of modifications in various respects, all without departing from the spirit of the invention. Accordingly, the drawings and description of the preferred embodiments are to be regarded as illustrative in nature and not restrictive.